Archive for Article

What is gray water, and can it solve the global water crisis?

Due to a one-two punch of a booming population and severe droughts across the globe, the Earth is in what the United Nations is calling a “water crisis”. It’s possible to make do with just a few gallons a day, as people do in many parts of the world, but households in the United States use an average­ of 400 gallons of water per day.

With a growing awareness of this disparity, some Americans are beginning to think about ways to cut down on their water usage. In some states — especially in the southeastern and western United States — residents don’t have a choice: Many state governments have issued bans on outdoor watering and are asking residents to take steps to cut their water by as much as 20 percent. Read more

Can the sun’s energy be used to clean water?

Water is essential to human life, and it’s no mystery that the sun plays an important role in the water cycle on our planet, as water moves from clouds to rain to rivers, lakes and oceans, and back again. Scientists have discovered several ways to use the sun’s energy and the processes of evaporation and condensation to help sanitize water and make it safe to drink.

One of the simpler methods involves the use of solar stills. One of the first solar stills was developed in the 19th century when mine owners in Chile faced the problem of providing drinking water for their workers; by using a sun-operated distilling plant with a large area of glassed-over wooden frames, they could evaporate the contaminated water, recondense it and produce up to 6,000 gallons (22,712 liters) of fresh water in a single day. Read more

No Wars for Water

Why Climate Change Has Not Led to Conflict

The world economic downturn and upheaval in the Arab world might grab headlines, but another big problem looms: environmental change. Along with extreme weather patterns, rising sea levels, and other natural hazards, global warming disrupts freshwater resource availability — with immense social and political implications. Earlier this year, the Office of the Director of National Intelligence published a report, Global Water Security, assessing hydropolitics around the world. In it, the authors show that international water disputes will affect not only the security interests of riparian states, but also of the United States.

In many parts of the world, freshwater is already a scarce resource. It constitutes only 2.5 percent of all available water on the planet. And only about .4 percent of that is easily accessible for human consumption. Of that tiny amount, a decreasing share is potable because of pollution and agricultural and industrial water use. All that would be bad enough, but many freshwater bodies are shared among two or more riparian states, complicating their management. Read more

Water and climate change: ‘Era of stable abundance is over’

As World Water Week draws to a close, water and climate expert Jens Berggren explains why climate change is already affecting our precious H2O.

DW: Can you explain the correlation between climate change and water?

Jens Berggren: That is actually a really big question, and it’s hard to answer, because it’s more a case of what is not the correlation. The teeth of climate change, how it will be experienced by people and plants and animals on our planet, that is to a very large extent, through water.

It’s changing the way water moves on our planet and how it behaves. Already today, some 90 percent of all natural disasters are water related; between 1992 and 2012, water related disasters affected 4.2 billion people. And the predictions for the future are that these extreme weather events will increase in both frequency and intensity. Read more

How Petersburg Was Saved from Floods

The Northern capital, built in the delta of Neva, always had uneasy relations with the river and the sea. For all its history the city has experienced more than 300 floods! The threat of flooding has always been real, and all this time rulers and scientists have devised ways to prevent destruction and sacrifice. This we tell in the next Water-gallery.

To find the correct solution to the problem, it was necessary to understand its causes. Why did the water in the Neva rise and fall upon the city? Who is to blame – the sea or the river? On this account for a long time there was no single point of view, and a variety of protection methods were offered. Read more